Speaking at the International Rural Network conference in Whyalla, Mr Cribb presented his ideas about the importance of algae farming for fuel, and fish farming for food.

Whilst the technology is already being used overseas, it is yet to be embraced in Australia, despite his argument that this was crucial for a sustainable future.

"We need to double food production worldwide to feed ten billion people by about the 2060's.

"The trouble with that is that everything we need to double food production is running out."

He said essential ingredients for food production, such as fresh water, land, oil, fertiliser, and stable climates, were depleting.

The solution? Algae.

He said algae could be grown, and used both for fuel and feed for aquaculture.

Passionate about the state's algae fuel potential, he said growing it in South Australia would involve sunlight, large areas of flat land, and salt water.

"People in Australia need to realise that we've got the largest resource of sunlight on earth.

"Sunlight grows crops, it grows things like algae."

He said for every hectare of algae grown, between 50 and 100 barrels of oil could be produced.

"You could probably grow the whole of South Australia's liquid fuel requirements.

"That's every car, every truck, every ship, every train and every plane, from an area no bigger than a single large sheep station."

Using algae to boost fish farming

The algae would also help feed an expanded fish farming industry, said Mr Cribb.

"To feed those fish you're going to have to grow algae, because it's going to be too expensive to feed them on grain."

He said renewable fish farming was crucial to feeding the country in the future, and compensating for dropping fish stocks.

"The world catch has been declining every year since 2004- we've already gone through the oceans."

Mr Cribb said consumers would need to diversify their fish diet, tossing aside popular varieties that are becoming increasingly scarce, and embracing the species that can grow well in the farming conditions.

"You can get 10 tonnes of barramundi from one hectare of pond, so it's a very high yielding and highly productive industry."

He said using algae to feed fish farms is the way of future.

"South Australia's already very good at farming fish, but the future aquaculture industry is going to be worth $5 billion- it's going to be bigger than beef, sheep, pork and poultry put together."

Not just a green pipe dream

Mr Cribb said the futuristic industries of growing algae for fuel and aquaculture feed were not just a pipe dream, but a 'reality' being explored around the world.

Other countries such as Israel, China and America were already embracing the possibilities of algae fuel, Mr Cribb explained.

He said in America, President Barrack Obama has been spending $500 million to keep the US air force in the air, and US Navy afloat, using algae fuels.

"There was a big American military exercise about a month ago, where every plane that took off from an aircraft carrier was fuelled by algae."

He said 'imagination and investment' was required to develop the industry in South Australia.

"We need the imagination to understand that South Australia is actually the best place in the world to do this, because you've got open skies, and more sunlight, than almost anywhere in Australia.

"There're a lot of very innovative farmers in South Australia, and I think some of them would think about growing water crops beside growing land crops."

He was optimistic agriculture industry leaders, and various levels of government, could see algae growth as 'the biggest opportunity the state has had'.

"Once people like that realise and get on board, they will make it happen.

"That is the opportunity of the future, instead of the big oil companies drilling for stuff, it is for farmers to actually grow it."